1. Field of the Invention
This invention relates to apparatus for indicating oiliness and stringiness of hair tresses and, more particularly, to apparatus for providing a relative indication of oiliness and stringiness of hair tresses under dynamic conditions.
2. Description of the Prior Art
One of the negative aspects of some hair conditioners and creme rinses is that they can make hair look "oily" or "stringy". There are times when women want their hair to be shiny, silky, or lustrous. Moreover, in conditioning shampoos, the amount and nature of the conditioner added to the shampoo is very critical and optimization is not an easy task. For this reason, several attempts have been made to determine the effect of various conditioners on hair tresses. For example, hair luster has been studied by measuring light reflected from hair tresses using a reflectometer. A change in luster after a hair tress has been treated by a creme rinse is measured by use of a Hunter-lab D40 Reflectometer in a mode normally used for measuring whiteness. In addition, investigators have examined many other ways for determining the amount of soil deposited on hair and the efficiency of various detergents for removing soil from the hair.
The aforementioned methods and apparatus are limited in accuracy and applicability. For example, the sensitivity of the reflectometer is quite low when blond hair is not used, and the hair tress is usually in a static position in a horizontal plane and not in a randomized and moving configuration. It has been determined that oiliness and stringiness of hair tresses are better tested under dynamic conditions that are closer to reality than measurements made on individual fibers.
Accordingly, it is desirable to arrange an instrument to accurately evaluate the relative oiliness and stringiness of hair tresses under dynamic conditions.